146 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
very slightly twisted; outer lip acute, sinus almost obsolete. Long., .34; 
lat., .1; long, aper., .15 in. (Gabb.) 
Type in State Geological Survey, Mollusca Survey Cabinet, No. 425. 
Type locality, Catalina Island, California. 
Range. Monterey to San Diego, California. 
Described as Mangilia hexagona . 
Cytharella aculea Dali, 1919 
Proceedings of the United States National Museum, 56:74. 
Shell small, purple-brown, banded with white, or varicolored; nucleus 
of one and a half, loosely-coiled, smooth, nuclear and four subsequent 
whorls; axial sculpture of six, somewhat sigmoid rounded ribs continuous 
up the spire, with excavated, much wider interspaces, with fine axial stria- 
tion, which slightly wrinkles the spirals; spiral sculpture of numerous 
sharp, often paired grooves separated by wider flattish interspaces, which 
are faintly marked by the axial striation; aperture narrow, anal sulcus 
conspicuous, outer lip thickened, smooth inside, pillar simple, canal hardly 
differentiated. Height of shell, 6; of last whorl, 3.5; diameter, 2 mm. 
(Dali.) 
Type in United States National Museum, No. 73994. Type locality, 
San Diego, California. 
Range. San Diego, California, to Cape San Lucas, Lower California. 
Cytharella hippolita Dali, 1919 
Proceedings of the United States National Museum, 56:76; PI. 22, figs. 6, 8. 
Shell small, slender, whitish, dark brown, or spirally banded with 
brown and white; nucleus with a very small, blunt, apical whorl, the 
succeeding whorl (worn in the specimens) probably feebly sculptured; 
subsequent whorls about five, with an appressed suture; spiral sculpture 
of very fine spiral striae, perceptible under the magnification, becoming 
coarser toward the canal; axial sculpture (including the terminal varix) 
of seven strong ribs with wider interspaces, slightly protractive anteriorly, 
continuous up the spire around which they show a slight twist, and ex¬ 
tending on the last whorl to the canal; aperture narrow, elongated, anal 
sulcus wide, shallow, outer lip thickened, smooth, internally, inner lip 
simple; canal hardly differentiated. Height of shell, 5.7; of last whorl, 
3.5; diameter, 2 mm. (Dali.) 
Type in United States National Museum, No. 127536. Type locality, 
shell drift, San Hipolite Point, Lower California. 
Range. San Diego, California, to Lower California. 
[1461 
